Change INVALID_[OID|TID] value.

OID 0 is a very valid oid. It's often used for the most important object of
the database: the root object. Using 0xffffffffffffffff leaves some space.

TID 0 is a very valid tid, for transactions back in unix year 0... or
ZODB tests. Using 0xffffffffffffffff leaves some space.

git-svn-id: https://svn.erp5.org/repos/neo/trunk@1977 71dcc9de-d417-0410-9af5-da40c76e7ee4

neo/protocol.py

@@ -97,8 +97,8 @@ cell_state_prefix_dict = {
 
 # Other constants.
 INVALID_UUID = '\0' * 16
-INVALID_TID = '\0' * 8
-INVALID_OID = '\0' * 8
+INVALID_TID = '\xff' * 8
+INVALID_OID = '\xff' * 8
 INVALID_PTID = '\0' * 8
 INVALID_SERIAL = INVALID_TID
 INVALID_PARTITION = 0xffffffff

neo/tests/testProtocol.py

@@ -18,6 +18,7 @@
 import unittest
 from neo.protocol import NodeTypes, NodeStates, CellStates
 from neo.protocol import ErrorCodes, Packets, Errors
+from neo.protocol import INVALID_TID
 from neo.tests import NeoTestBase
 
 class ProtocolTests(NeoTestBase):
@@ -241,7 +242,7 @@ class ProtocolTests(NeoTestBase):
 
     def test_32_askBeginTransaction(self):
         # try with an invalid TID, None must be returned
-        tid = '\0' * 8
+        tid = INVALID_TID
         p = Packets.AskBeginTransaction(tid)
         self.assertEqual(p.decode(), (None, ))
         # and with another TID